PROJECT SUMMARY/ ABSTRACT Cardiovascular disease (CVD) is the leading cause of mortality among U.S. adults, and hypertension (HTN) is the strongest risk factor for CVD. Under recently introduced guidelines, an estimated 46% of U.S. adults ? or 103.3 million people ? have HTN. HTN is not equally distributed through the population, and disease onset is strongly predicted by race/ethnicity, socioeconomic position (SEP), and gender. Non-Hispanic blacks (NHB), certain Hispanic sub-populations (e.g., middle-age/elderly, Puerto Ricans, Dominicans), and low SEP individuals are at higher risk of HTN than non-Hispanic whites (NHW), in general. Additionally, the prevalence of HTN in both Hispanic and NHB females is higher than that of their male counterparts; this is in contrast to NHW, among whom differences in prevalence by sex vary by age. Although a number of factors have been identified as possible contributors to HTN-related health disparities (including genetic and behavioral factors), these risk factors do not fully explain HTN disparities, and social determinants of health have been suggested to explain differential health outcomes despite shared genetic ancestry or similar health behaviors. Work is a critical determinant of health, and a growing body of evidence suggests a positive relationship between work hour patterns and HTN onset, particularly among work groups who may experience less desirable working conditions and arrangements. However, little is known about the sociodemographic distribution of work hours (WH) or HTN- related occupational risks. We will address these limitations by describing WH trajectories in a representative sample of U.S. workers by race/ethnicity and gender (Aim 1) and assessing the effects of longitudinal, time- varying WH trajectories on incident HTN by race/ethnicity and gender (Aim 2). Next, we will estimate the influence of WH and race/ethnicity on HTN-related health decline by gender (Aim 3). These aims will be executed in a data set constructed by merging a nationally representative panel study (Panel Study of Income Dynamics, or PSID) with job-characteristics data sponsored by the U.S. Department of Labor (U.S. Occupational Information Network, or O*NET) across 30 years to yield one of the most comprehensive data sets to date for the examination of work-related factors on HTN incidence and HTN-related health decline. The proposed project supports the National Heart, Lung and Blood Institute?s focus on investigating factors that account for differences in health among populations. Findings from this cost-effective, innovative study will broaden our scientific understanding of the influence of WH on HTN incidence and related health decline in vulnerable populations and could have substantial Research to Practice (r2p) implications across multiple programmatic and policy arenas, including healthcare, education, and workplace wellness. Workplace practices, including long WH, can be addressed (at least partially) through workplace and policy interventions. Policies to encourage healthier work environments ? especially for jobs likely to be held by the most disadvantaged demographic groups ? should be proposed as part of a comprehensive strategy to reduce and, ultimately, eliminate the extent of these health inequalities.